#!/usr/bin/env bash
# Assert that R8 left the names JNI resolves at runtime alone.
#
# iperf_jni.c looks up the callback methods by name with GetMethodID. R8 renames
# by default, and a renamed callback does not fail the build — it produces an
# APK that aborts on the first callback of every test:
#
#   NoSuchMethodError: no non-static method "Lp0;.onOutput(Ljava/lang/String;)V"
#
# That shipped once. Building the release APK is not enough to catch it, because
# the build succeeds; this reads R8's own mapping file and checks the names
# survived. Run after `flutter build apk --release`.

set -euo pipefail

MAPPING="${1:-build/app/outputs/mapping/release/mapping.txt}"
APK="${2:-build/app/outputs/flutter-apk/app-release.apk}"

if [[ ! -f "$MAPPING" ]]; then
    echo "FAIL: no R8 mapping at $MAPPING"
    echo "      Run 'flutter build apk --release' first. If the release build"
    echo "      no longer minifies, this check is meaningless — say so"
    echo "      explicitly rather than deleting it."
    exit 1
fi

failed=0

# A class kept by name maps to itself: "a.b.C -> a.b.C:".
require_class_kept() {
    local fqcn="$1"
    if grep -qF -- "$fqcn -> $fqcn:" "$MAPPING"; then
        echo "  ok    class  $fqcn"
    else
        echo "  FAIL  class  $fqcn was renamed or removed"
        grep -F -- "$fqcn ->" "$MAPPING" | head -3 | sed 's/^/          got: /' || true
        failed=1
    fi
}

# A method kept by name ends with "-> <name>".
require_method_kept() {
    local signature="$1" name="$2"
    if grep -qE -- "$signature.*-> ${name}\$" "$MAPPING"; then
        echo "  ok    method $name"
    else
        echo "  FAIL  method $name was renamed"
        grep -E -- "$signature" "$MAPPING" | head -3 | sed 's/^/          got: /' || true
        failed=1
    fi
}

echo "Checking JNI-visible names in $MAPPING"

require_class_kept 'com.novoyuuparosk.iperf3gui.IperfRunner'
require_class_kept 'com.novoyuuparosk.iperf3gui.IperfRunner$IperfCallback'
require_class_kept 'com.novoyuuparosk.iperf3gui.IperfRunner$MainThreadCallback'

# Resolved by iperf_jni.c on the concrete callback object's class.
require_method_kept 'void onOutput\(java\.lang\.String\)' 'onOutput'
require_method_kept 'void onError\(java\.lang\.String\)' 'onError'
require_method_kept 'void onComplete\(\)' 'onComplete'

# Native methods are NOT checked against mapping.txt: R8 only emits entries for
# members it has line-number info or a rename for, and a native method has no
# body, so it is absent whether or not it was renamed. Absence would prove
# nothing. Check the DEX string pool instead — a surviving name is interned
# there, a renamed one is not.
check_dex_names() {
    local apk="$1"
    shift
    if [[ ! -f "$apk" ]]; then
        echo "  skip  DEX name check: no APK at $apk"
        return
    fi
    local tmp
    tmp="$(mktemp -d)"
    trap 'rm -rf "$tmp"' RETURN
    if ! unzip -o -q "$apk" 'classes*.dex' -d "$tmp" 2>/dev/null; then
        echo "  FAIL  could not extract classes*.dex from $apk"
        failed=1
        return
    fi
    # Dump the string pool once to a file, then grep the file. Never
    # `... | strings | grep -q`: grep -q exits at the first match, SIGPIPEs
    # strings, and `set -o pipefail` reports the whole pipeline as failed — so
    # a name found early "fails" and one found late passes. That flakiness cost
    # an afternoon; leave the intermediate file in place.
    cat "$tmp"/classes*.dex | strings > "$tmp/dex-strings.txt"

    local name
    for name in "$@"; do
        if grep -qxF -- "$name" "$tmp/dex-strings.txt"; then
            echo "  ok    native $name"
        else
            echo "  FAIL  native $name is absent from the DEX string pool"
            failed=1
        fi
    done
}

check_dex_names "${2:-build/app/outputs/flutter-apk/app-release.apk}" \
    runIperfLive forceStopIperfTest setTempDir isTestRunning

if [[ $failed -ne 0 ]]; then
    echo
    echo "R8 renamed something JNI resolves by name. The release APK will abort"
    echo "on the first callback. Fix android/app/proguard-rules.pro."
    exit 1
fi

echo "All JNI-visible names survived minification."